From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36692) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fwpwh-0004Fz-RO for qemu-devel@nongnu.org; Mon, 03 Sep 2018 10:35:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fwpwc-0000YQ-Lp for qemu-devel@nongnu.org; Mon, 03 Sep 2018 10:35:15 -0400 From: Alberto Garcia Date: Mon, 3 Sep 2018 17:34:08 +0300 Message-Id: In-Reply-To: References: In-Reply-To: References: Subject: [Qemu-devel] [PATCH v2 10/10] block: Allow changing 'force-share' on reopen List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Alberto Garcia , qemu-block@nongnu.org, Max Reitz , Kevin Wolf 'force-share' is one of the basic BlockdevOptions available for all drivers, but it's not handled by bdrv_reopen_prepare() so any attempt to change it results in a "Cannot change the option" error: (qemu) qemu-io virtio0 "reopen -o force-share=on" Cannot change the option 'force-share' Since there's no reason why we shouldn't allow changing it and the implementation is simple let's just do it. It's worth noting that after this patch the above reopen call will still return an error -although a different one- if the image is not read-only: (qemu) qemu-io virtio0 "reopen -o force-share=on" force-share=on can only be used with read-only images Signed-off-by: Alberto Garcia Cc: Max Reitz --- block.c | 30 ++++++++++++++++++++++++------ include/block/block.h | 1 + 2 files changed, 25 insertions(+), 6 deletions(-) diff --git a/block.c b/block.c index 3865ef8517..7ee29ec9eb 100644 --- a/block.c +++ b/block.c @@ -788,6 +788,18 @@ static BlockdevDetectZeroesOptions bdrv_parse_detect_zeroes(QemuOpts *opts, return detect_zeroes; } +static bool bdrv_parse_force_share(QemuOpts *opts, int flags, Error **errp) +{ + bool value = qemu_opt_get_bool_del(opts, BDRV_OPT_FORCE_SHARE, false); + + if (value && (flags & BDRV_O_RDWR)) { + error_setg(errp, BDRV_OPT_FORCE_SHARE + "=on can only be used with read-only images"); + } + + return value; +} + /** * Set open flags for a given discard mode * @@ -1373,12 +1385,9 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, drv = bdrv_find_format(driver_name); assert(drv != NULL); - bs->force_share = qemu_opt_get_bool(opts, BDRV_OPT_FORCE_SHARE, false); - - if (bs->force_share && (bs->open_flags & BDRV_O_RDWR)) { - error_setg(errp, - BDRV_OPT_FORCE_SHARE - "=on can only be used with read-only images"); + bs->force_share = bdrv_parse_force_share(opts, bs->open_flags, &local_err); + if (local_err) { + error_propagate(errp, local_err); ret = -EINVAL; goto fail_opts; } @@ -3201,6 +3210,14 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, goto error; } + reopen_state->force_share = + bdrv_parse_force_share(opts, reopen_state->flags, &local_err); + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + goto error; + } + /* All other options (including node-name and driver) must be unchanged. * Put them back into the QDict, so that they are checked at the end * of this function. */ @@ -3351,6 +3368,7 @@ void bdrv_reopen_commit(BDRVReopenState *reopen_state) bs->open_flags = reopen_state->flags; bs->read_only = !(reopen_state->flags & BDRV_O_RDWR); bs->detect_zeroes = reopen_state->detect_zeroes; + bs->force_share = reopen_state->force_share; /* Remove child references from bs->options and bs->explicit_options. * Child options were already removed in bdrv_reopen_queue_child() */ diff --git a/include/block/block.h b/include/block/block.h index f71fa5a1c4..a49a027c54 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -185,6 +185,7 @@ typedef struct BDRVReopenState { BlockDriverState *bs; int flags; BlockdevDetectZeroesOptions detect_zeroes; + bool force_share; uint64_t perm, shared_perm; QDict *options; QDict *explicit_options; -- 2.11.0